Abstract This 3-year project etiology of suicidal behavior during adolescence and emerging adulthood is in response to the Centers for Disease Control and Prevention RFA-CE-10-005 Research Grants for Preventing Violence - and Violence Related Injury that calls for etiologic research on suicidal behavior. Our primary research objective is to identify variables that decrease risk for suicide attempts in young people ages 12 to 25. We will examine three types of variables that decrease risk: 1) promotive factors that decrease risk directly, that is they show a direct, inverse relationship to SA; 2) protective factors that serve as a buffer against risk by moderating (lowering) the potency of risk factors; 3) variables that are both promotive and protective. Informed by a social connectedness framework, we will focus on promotive and protective effects of connectedness to peers, school, parents, and family. We will also examine promotive and protective effects of social capital, a measure of the connectedness within a community. Finally, we will investigate whether or not the promotive and/or protective effects of connectedness to parents, etc. assessed during adolescence endure into emerging adulthood. To accomplish these goals, we will analyze two large prospective datasets of adolescents and emerging adults assessed for the Collaborative Study on the Genetics of Alcoholism (COGA). We will also analyze measures of social capital derived through external data sources (e.g., Area Resource File). In Aim 1, we will test an etiological model of risk for suicidal behavior in youth. In Aim 2, we will examine the potentially promotive effects and protective effects of connections with peers, school, parents, and family. Protective effects will be examined by testing moderators of the risk factors confirmed in the Aim 1 analyses. In Aim 3, we will examine the promotive and protective effects of social capital. We will perform the analyses primarily using mixed effects models and structural equation models. The project will be carried out by an experienced multi-disciplinary research team. Results will be disseminated through peer-reviewed research papers, conference presentations, and twice-yearly suicide prevention meetings held in New York State (dissemination conferences) where non-technical presentations will be made to general audiences. PUBLIC HEALTH RELEVANCE: While most studies of suicidal behavior focus on risk factors, the goal of this project is to identify variables that decrease risk for suicide attempt during adolescence (ages 12 to 17) and emerging adulthood (ages 18 to 25), a time in the life course when the prevalence of suicide attempts peak and represents the most potent risk factor for eventual suicide. Informed by a social connections framework for suicide research and prevention, we will study the extent to which connectedness to peers, school, parent, and family lowers risk for a suicide attempt and whether or not the risk-lowering effects of these connections endures into emerging adulthood. We will also examine whether or not social capital, a measure of connectedness within a community, serves to lower adolescents and emerging adults risk for making a suicide attempt, with implications for developing strategies to strengthen young peoples' connections with others in order to prevent suicidal behavior.